For the fonts, you can go in the Control Center, in Appearance, Fonts tab, click on "details" and set the resolution. By default, it should be set on automatic with 96 dpi. Toggle the automatic option and select a value higher than 96 dpi to have bigger fonts.

For the icons, I don't think so, or at least not on a general level. In the file manager (Caja), you can use the zoom option to have bigger icons. This will affect the file manager and the desktop but not the icons in toolbars and such.